Genetic information is stored in DNA, passes through RNA and is expressed as protein. The RNA is more than a passive intermediary in this (slightly oversimplified) scheme. The primary transcript of the gene, a base-for-base copy of the DNA coding strand, is in the majority of cases modified before playing its biological role. The modifications are widespread in nature, being found in procaryotic and eukcaryotic cells and in all major classes of RNA-ribosomal, messenger and transfer RNA. The modifications may be of several kinds: individual nucleotides may be chemically substituted; sequences may be added to or removed from either or both termini; and internal sequences may be excised and the remaining parts religated. This latter variety, 'splicing', has not been observed in procaryotes. The significance of the modification is profound, ranging from stabilization, through alteration of the RNA's function, to conversion of an inactive precursor into with a mature functional product. The objective of the RNA Processing meeting is to bring together the increasing number of people working in this expanding field, so that they may exchange recent data and techniques and critically evaluate the status and progress of research in this area. No comparable forum for such a gathering exists, and the field should benefit greatly from the planned meeting. This application requests funds for 3 consecutive annual meetings since it is expected that the RNA processing field will continue to expand and flourish for several years to come.